The first rule in breathing is to “Keep Breathing”. This is a good idea because if you stop breathing you will surely die! In Tai Chi we do not attempt to hold our breath. Instead, we attempt to never hold our breath and always be constantly inhaling or exhaling. The constant change of inhale and exhale is the constant change of Yin and Yang in the cosmos and in our bodies. Being able to connect our breathing with our movements and maintain awareness of our breathing from the beginning of our form until you enter a profound state of moving meditation.
Yin and Yang are relative. They depend on each other. The define each just like and a husband and wife define each other. They only exist in relationship to one another. To identify Yin, you must also identify Yang. Nothing is only Yin or Yang. Nothing is also all the time always Yin or always Yang. Whether something is said to be Yin or Yang depends on what you are comparing it to and along what metric are you making the comparison.
For example, outside it is sunny and bright, or Yang, compared to inside the house where it is shady and dark, or Yin. However, inside the house the table top is Yang or bright and under the bed is Yin or dark.
In this way we can discuss and define Yin and Yang in breathing in multiple ways.
In Tai Chi Chuan we wish to breathe naturally in harmony with our body. If we are tense and upset or afraid it can be difficult to breathe deep. If our mind is racing or distracted it can be impossible to focus on your breathing. If you are a beginner learning your first movements your mind might be too busy to both remember what you are doing and your breathing. After you have learned and can easily remember your movements you can start to focus on your breathing.
In general, you want to inhale as your arms are withdrawing and / or when the chest is expanding. Inhaling when the chest is expanding and exhaling when the chest is contracting is natural. As the ribcage expands it is easy for the lungs to expand and open permitting a deeper breath. When our ribcage contracts it is natural to exhale as the lungs are compressed by the shrinking ribcage. We want to exhale as we reach out or push.
When we use force and engage the muscles on the front of the body, the chest and abdominal muscles, the ribcage, and the torso are getting smaller because these muscles are contracting. If we exhale as we release our power it is healthier for our Heart and Lungs and it is more harmonious for the development of power.
Depending on the pace at which you practice you might feel like taking more than one breath with a single long movement. During Form practice there is nothing wrong with that. Sometimes our body just isn’t ready for long, deep breathes. When that is the case simply focus on the movements and just breath as deep as you can and relax with every breath. As you relax your mind and body your breathing will become longer, slower, and far deeper. Combining slow moment and deep breathing is incredibly relaxing and relaxing is the best way to prevent all the negative effects of stress.